DHEA AND THE EFFECTS OF AGING

Luke Rainwater








Outline: Click on a topic to go to that section
WHAT IS DHEA?
DHEA LEVELS
AGING
STRESS CONTROL
WEIGHT CONTROL
CANCER
PURPOSE
SIDE EFFECTS
PRODUCT
CONCLUSION
References





Many people have searched the world in hope of a cure for the effects of aging. Unfortunately, they have never found the fountain of youth, but what they discovered was Dehydroepiandrosterone (DHEA), possibly the next best thing. All the facts of DHEA have not been drawn into a concrete conclusion, but scientists already have evidence that suggest it aids in stress and weight control, cancer, and other negative effects of aging. As a person increases in age, their level of DHEA decreases, causing health and aging problems. Therefore, claims have been made that supplements of DHEA may have health-enhancing or anti-aging properties.

Numerous claims have been made by distributors in an effort to persuade the public to buy DHEA supplements. Most of the claims appear too good to be true, but some of them are correct. Many experiments have shown the importance of maintaining a proper body level of the DHEA supplements. The suggested facts of DHEA that are known today will lead to the concrete conclusions of the future.

As it now stands, the role of DHEA as a treatment in humans has not been adequately studied. However, there is supportive epidemiological data associating the decline of DHEA levels with the number of diseases of aging. Most of this data was collected through the study of rodents, and is not applicable evidence to support its effect on humans.

WHAT IS DHEA?

Dehydroepiandrosterone, or DHEA (C-19-H-28-O-2) is a steroid hormone produced in the adrenal glands. It is the most abundant steroid in the bloodstream, and the most naturally-occurring hormone in the human body. DHEA is the precursor for the manufacturing of many other hormones, such as: estrogen, testosterone, progesterone, cortisone, and others. These hormones are then used for the energy, vitality, and the natural support of most bodily functions that involve the endocrine system. Fat and mineral metabolism, stress control, and maintenance of the male and female characteristics are partially regulated by the DHEA level. Usually, the higher the level of DHEA, the healthier the individual is (http://www.smartbasic.com/glos.nutrients/dhea.glos.html).

DHEA LEVELS

The constant changing of DHEA levels begins in utero. It is the most abundant product of the fetal adrenal gland because secretion from the adrenal cortex is very high. After birth, the level drops sharply and remains low during childhood. It rises before puberty, and reaches high levels once again during young adulthood. From then on it progressively declines at a rate of 2% per year (Hornsby, 1995). The lower the level becomes, the more prone a person is to sickness.

AGING

Many claims have been made that state that DHEA can be used to treat the effects of aging. The truth is that DHEA plays several significant roles in the aging process, but its major biological function has yet to be pointed out. As I stated earlier, as a person increases in age the presence of DHEA in the body decreases, but it remains just as important for everyday functioning. Therefore, taken as a supplement it could possibly enable a person to maintain DHEA levels that the body needs for superb functioning.

Research shows that when DHEA levels decline with age, it increases the incidence of killer diseases. When the human body is about twenty years of age DHEA is abundant. But by the age of eighty, blood levels have declined as much as ninety-five percent, about ten to twenty percent of the amount at twenty years of age (DHEA-Sex Drive, Weight Loss, Youth Hormone). Maintianing proper levels of DHEA is claimed to have an effect on a person's appearance. The claim cannot be proved for humans, but suggested facts can be aquired from rodent studies. DHEA has been know to extend rodent life spans up to 50%, and make them look younger. The animals that received DHEA supplements retained their sleek black hair, while the others turned gray and course (http://www.ceri.com/dhea.htm).

STRESS CONTROL

Claims have been made that since DHEA is a cholesterol metabolite, it aids in the relief of stress. These claims also state that stress stimulates the body to secrete cortisol and dehydroepiandrosterone-sulfate (DHEAS), the sulfated-form of DHEA (http://arsunxsvr.aeiveos.com/diet/dhea/94293507/html). In addition, anytime there is a disturbed balance between these hormones it will cause various stress disorders. Consequently, supplementing DHEA would prevent the balance from being disturbed and relieve the person from stress disorders.

The truth is that DHEA does play a major role in stress control. Stress stimulates the body to secrete cortisol and DHEA, and increases the incidence of infectious diseases (Bernton, Hoover, Galloway, and Popp, 1995). DHEA interacts with serum cortisol to maintain a balance between them. A disturbance between the two can lead to stress disorders. During severe stressors, such as critical illness, cortisol is increased, and DHEA is suppressed (Bernton, Hoover, Galloway, and Popp, 1995). DHEA has an anxiolytic effect on stress. These effects go to show that DHEA works to terminate the stress response, depending on the amount of DHEA.

In a study in Pharmacology Biochemistry and Behavior (Melchior and Ritzmann, 1994), mice were tested in what was called the plus maze to determine if DHEA had an anxiolytic or anxiogenic effect on stress. The plus maze is made of black Plexiglas consisting of two opposite-facing open arms and two opposite-facing closing arms. The walls of the closed arms are clear and separated. The whole maze is mounted on a base that makes it 38cm off of the floor. For the actual test, a mouse was injected with Ethanol and placed at one end of one of the open arms. The scientists recorded the time it took to leave the start position, and the time it took until the mouse entered half way into one of the closed arms. This is when the three minute test session began. The scientists recorded the number of times the mouse entered into the open arms . The mouse had to place at least two paws in an entry for it to be defined. The study resulted in an anxiolytic effect because of its effect on the immune system and its ability to weaken a stress-induced increase in corticosterone levels. The study suggests that there are numerous situations where it could possibly be productive for a person to take DHEA to relieve a major stress response.

WEIGHT CONTROL

The population of today is concerned about being overweight. Numerous claims have been made stating that DHEA aids in weight control. The possibility that DHEA can control weight can be demonstrated through the use of the Zucker fatty rat, an animal model of genetic obesity. This is a great subject to experiment, considering that man controls his body weight with a substantial genetic component, similarly to the rat (Wright, Porter, Browne, and Svec, 1992). Hyperphagia, insulin resistance, and hypercorticosteronemia are some of the other characteristics that the obesity of the Zucker fatty rat and human obesity have in common (Wright, Browne, Svec, and Porter, 1993).

The antiobesity effects of DHEA have yet to be fully resolved, but it is known that hormones produced from DHEA influence fat and mineral metabolism. Dr. A. Schwartz, a researcher at Temple University, has proven DHEA's effectiveness in weight control in rodents. G6PD (glucose-6-phosphate-dehydrogenase) is an enzyme that is essential for fat tissue production. DHEA has an ability to block this enzyme and cause the reduction of body fat. The blocking of G6PD redirects glucose from anabolic fat-production into catabolic energy metabolism, thus creating a leaner metabolism. Therefore, it is believed that DHEA is a method of weight control that is not dependent upon a person's diet (DHEA-Sex Drive, Weight Loss, Youth Hormone). Dr. Terrence T. Yen studied the effect of DHEA on genetically obese mice. The mice that received DHEA ate normally, but remained thin and lived longer than the control mice (http://www.ceri.com/dhea.htm).

In a study in the International Journal of Obesity (Wright, Porter, Browne, and Svec, 1992), obese and lean Zucker rats were randomly divided into groups and weighed. Each rat was injected with either dimethylsulphoxide (DMSO), dexamethasone, DHEA, or both dexamethasone and DHEA. Fat was aspirated from each sample and the supernatants were assayed for enzyme activity and protein. Tyrosine aminotransferase (TAT) and Ornithine decarboxylase (ODC) were measured and aliquots of each supernatant were incubated. The samples were sealed and kept in a dark place overnight, and then measurements were made of the protein, (TAT), and (ODC).

The results showed that the DHEA was exerting an inhibitory effect on the action of the glucocorticoids, and may have the potential to regulate weight in humans. However, studies involving humans should be done before there is proof that people should take DHEA in order to lose weight. If human studies ever depict that DHEA can be used for controlling the weight of humans, then it could be used for their personal dietary gains.

CANCER

Numerous claims have been made about DHEA's prevention of cancer in humans. Although DHEA is only partially understood in humans, supplementing DHEA has been shown to have anti-cancer influences in rodents. For example, Dr. A Schwartz found that supplemental DHEA would protect cell cultures from the toxicity of carcinogens. Ordinarily, cell cultures would have responded to the carcinogens with transformations, mutations, and a high rate of cell death, but the supplemental DHEA with the carcinogens produced no negative effects to the cell cultures. Also, Schwartz later tested laboratory mice with supplemented DHEA. When the breast-cancer-prone mice were given DHEA they had no tumors after eight months. But the control mice were "getting cancer left and right." Nevertheless, it is still not known today whether or not the successes achieved in animals will be the same for humans (http://www.ceri.com/dhea.htm).

DHEA aids in the prevention of cancer in rodents. Low circulating levels of DHEA have been associated with a higher incidence of breast cancer in women (Li, Yan, Belanger, and Labrie, 1993). DHEA has been shown to affect the growth of both human breast cancer cell lines and rat mammary carcinomas (Brignardello, Cassoni, Migliardi, Pizzini, Di Monaco, Boccuzzi, and Massobrio, 1994-1995).

In a study performed in Breast Cancer Research and Treatment (Li, Yan, Belanger, and Labrie, 1993-1994), female Sprague-Dawley rats were used to show how the level of DHEA relates to the risk of breast cancer. The study demonstrated how treatment with increasing serum levels of DHEA caused a progressive inhibition of tumor development from 68% bearing tumors in control animals to 22% and 11%. The rats were divided into seven groups with forty rats per group. The animals of the first group were ovariectomized while the intact animals received doses of DHEA administered in Silastic implants. Seven days later they administered dimethylbenz(a)anthracene (DMBA), and tumor development was monitored every three weeks . The results of the study show that 68% of the intact rats had developed palpable mammary carcinoma while only 2.7% of the ovariectomized animals had detectable tumors. The percentage of animals bearing mammary carcinoma 104 days after DMBA administration was reduced from 68% to 22%, to 11%, and 3.8%. The study's outcome demonstrates that circulating levels of DHEA compared to those observed in normal adult premenopausal women create an inhibitory effect on the development of mammary carcinoma.

PURPOSE

The purpose of the treatment of DHEA supplements is to maintain the appropriate level of DHEA in the bloodstream throughout a person's lifetime. Keeping the level at a constant can aid in negative effects of aging and possibly prevent the occurrence of killer diseases. Until recently the function of this steroid was given little attention, but research is now being performed to discover all of the facts about DHEA. Until the research of the effects of DHEA on humans is further developed, the purpose and benefit of the treatment cannot be clarified.

SIDE EFFECTS

There have been no discovered side effects of DHEA supplements at low level testing. Prudent use of the product may be warranted, but extreme caution should be taken until more results are known. You should not take the product if you are under forty, pregnant, nursing, capable of bearing children, or taking any prescription medication, including hormone products. If you are suffering from a disease you should consult a physician before using this product.

PRODUCT

The information for this product is being presented to the media by different distributors and manufacturers of the product. The presentations of the product are both informative and persuasive. DHEA can be purchased in a variety of amounts and prices. A 10 mg bottle containing ninety capsules cost $9.95. A more potent bottle of 25 mg containing 180 capsules cost $28.95. Finally, a 50 mg bottle containing 180 capsules cost $47.95 (httpp://www.smartbasic.com/glos.nutrients/dhea.glos.html). Most of the displays of DHEA are for the purpose of advertising and making money. On the other hand, there are certain research institutions that are providing information on the product for the advancement of medical facts.

CONCLUSION

Dehydroepiandrosterone is the most naturally-occurring hormone in the human body. It's level in the bloodstream decreases with age, but can be maintained through DHEA supplements. DHEA has been shown to aid in stress and weight control, cancer, and other negative effects of aging in rodents. All of the facts about DHEA are not yet known for humans, but the research of the steroid is in progress. The latest sources conclude that the role of DHEA in the aging process or as a predictor of life expectancy cannot have a definite statement until more data is acquired (Vermeulen, 1995). Not enough information has been given about the effect of DHEA on stress and weight control, cancer, and other negative effects of aging to enable a person to make a positive decision on whether or not they should use DHEA. Up until this time there have been no adverse effects discovered. However, a consumer should never misuse the product, and should follow all warning instructions.

References

Barrett-Connor, E., Goodman-Gruen, D. The Epidemiology of DHEAS and Cardiovascular Disease: Dehydroepiandrosterone And Aging. Annals of the New York Academy of Sciences. 774: 259-270, 1995 Dec 29.

Bernton, E., Hoover, D., Galloway, R. & Popp, K. Adaptation to Chronic Stress in Military Trainees: Adrenal Androgens, Testosterone, Glucocorticoids, IGF-1, and Immune Function: Dehydroepiandrosterone And Aging. Annals of the New York Academy of Sciences. 774: 217-218. 1995 Dec 29.

Hornsby, P.J. Biosynthesis of DHEAS by the Human Adrenal Cortex and Its Age- Related Decline: Dehydroepiandrosterone And Aging. Annals of the New York Academy of Sciences. 774: 29-31, 1995 Dec 29.

Li, S., Yan, X., Belanger, A., & Labrie, F.. Prevention by dehydroepiandrosterone of the development of mammary carcinoma induced by 7,12-dimethylbenz(a)anthracene (DMBA) in the rat. Breast Cancer Research and Treatment 29: 203-217, 1993.

Majewska, M.D. Neuronal Actions of Dehydroepiandrosterone: Possible Roles in Brain Development, Aging, Memory, and Affect: Dehydroepiandrosterone And Aging. Annals of the New York Academy of Sciences. 774: 111, 1995 Dec 29.

Melchior, C.L., & Ritzmann, R.F. Dehydroepiandrosterone Is an Anxiolytic in Mice on the Plus Maze. Pharmacology Biochemistry and Behavior, Vol. 47, No. 3, pp. 437-441, 1994.

Vermeulen, A. Dehydroepiandrosterone Sulfate and Aging. Dehydroepiandrosterone And Aging. Annals of the New York Academy of Sciences. 774: 124. 1995 Dec 29.

Wright, B.E., Porter, J.R., Browne, E.S., & Svec, F. Antiglucocorticoid action of dehydroepiandrosterone in young obese Zucker rats. Internation Journal of Obesity (1992) 16, 579-583.

Wright, B.E., Browne, E.S., Svec, F., & Porter, J.R. Divergent Effect of Dehydroepiandrosterone on Energy Intakes of Zucker Rats. Physiology & Behavior, Vol. 53, pp. 39-43, 1993.

 

 

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